Avalanche Forecast
Issued: Nov 30th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
ghelgeson,
Avalanche Canada
Avoid wind exposed features where stiff storm slabs are likely to be found. Observations are very sparse right now, if you've been out please submit a report to the Mountain Information Network.
Summary
Confidence
Low - Uncertainty is due to the limited number of field observations. Uncertainty is due to the extreme variability of wind effect on the snowpack.
Weather Forecast
The freezing level is expected to rise dramatically Tuesday evening.
MONDAY NIGHT: Freezing level at valley bottom, moderate to strong west/southwest wind, trace of snow expected.
TUESDAY: Overcast, freezing level climbing, potentially as high as 1700 m in the afternoon, strong to extreme southwest wind, trace of snow possible at upper elevations, rain falling at lower elevations in the afternoon. The freezing level is expected to climb to about 3000 m Tuesday night.
WEDNESDAY: A few clouds in the AM with cloud cover increasing throughout the day, freezing level holding around 2500 m, strong to extreme south/southwest wind, no precipitation expected.
THURSDAY: Broken cloud cover, freezing level at valley bottom, moderate to strong southwest wind, 1 to 5 cm of snow possible.Â
Avalanche Summary
New snow and wind Saturday night through Sunday night likely formed fresh storm slabs at and above treeline. Â
Observations are very limited but the combination of snow and wind over the past few days has almost certainly formed wind slabs in open terrain. On Thursday there were reports of some small (size 1) wind slabs on wind-loaded east aspects.
Please submit your observations to the Mountain Information Network!
Snowpack Summary
The storm produced about 15 to 50 cm of new snow with areas in the far north of the region receiving the bulk of the precipitation. The wind effect is thought to be extensive. See this MIN from a few days ago which does a great job of showing the effect of the wind.
Heavy wind effect seems to be the theme from last week, and that is expected to continue into this week.
Snowpack depths range from 60 cm in eastern parts of the region up to over 100 cm in western parts of the region. Lower elevation terrain may still be below the threshold for avalanches. Reports suggest the bottom half of the snowpack consists of crusts, and in some cases some weak snow may be developing around these crusts. This will be a layer to monitor as the season progresses.
Terrain and Travel
- Avoid freshly wind loaded terrain features.
- Seek out sheltered terrain where new snow hasn't been wind-affected.
- Be especially cautious near rock outcroppings, on steep convexities and anywhere the snowpack feels thinner than average.
Problems
Storm Slabs
15 to 50 cm of storm snow fell across the region over the last few days. Careful with the new storm snow, especially at upper elevations. Large human triggered storm slabs remain likely.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 1st, 2020 4:00PM
